Function svec_cast_float8arr

methods/svec/src/pg_gp/operators.c:560–615

* svec_cast_float8arr - turns a float8 array into an svec */

 *  svec_cast_float8arr - turns a float8 array into an svec
 */
Datum svec_cast_float8arr(PG_FUNCTION_ARGS) {
	ArrayType *A_PG = PG_GETARG_ARRAYTYPE_P(0);
	SvecType *output_svec;
	float8 *array_temp;
	bits8 *bitmap;
	int bitmask;
	int i,j;

	if (ARR_ELEMTYPE(A_PG) != FLOAT8OID)
		ereport(ERROR,
			(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
			 errmsg("svec_cast_float8arr only defined over float8[]")));
	if (ARR_NDIM(A_PG) != 1)
		ereport(ERROR,
			(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
			 errmsg("svec_cast_float8arr only defined over 1 dimensional arrays")));

	/* Extract array */
	int dimension = ARR_DIMS(A_PG)[0];
	float8 *array = (float8 *)ARR_DATA_PTR(A_PG);

	/* If the data array has NULLs, then we need to create an array to
	 * store the NULL values as NVP values defined in float_specials.h.
	 */
	if (ARR_HASNULL(A_PG)) {
		array_temp = array;
		array = (double *)palloc(sizeof(float8) * dimension);
		bitmap = ARR_NULLBITMAP(A_PG);
		bitmask = 1;
		j = 0;
		for (i=0; i<dimension; i++) {
			if (bitmap && (*bitmap & bitmask) == 0) // if NULL
				array[i] = NVP;
			else {
				array[i] = array_temp[j];
				j++;
			}
			if (bitmap) { // advance bitmap pointer
				bitmask <<= 1;
				if (bitmask == 0x100) {
					bitmap++;
					bitmask = 1;
				}
			}
		}
	 }

	/* Create the output SVEC */
	SparseData sdata = float8arr_to_sdata(array,dimension);
	output_svec = svec_from_sparsedata(sdata,true);

	if (ARR_HASNULL(A_PG))
		pfree(array);

	PG_RETURN_SVECTYPE_P(output_svec);
}

PG_FUNCTION_INFO_V1( svec_cast_positions_float8arr );